1. Field of the Invention
The present invention relates to a shift lever apparatus which is mounted in a vehicle in order to change a shift range of a transmission.
2. Description of the Related Art
Among apparatuses for shifting between a plurality of shift ranges preset in an automatic transmission of a vehicle, there is a shift lever apparatus which rotates a shift lever mechanically connected to the automatic transmission so as to shift the shift lever to a shift range corresponding to the rotation position (shift position).
Moreover, this type of shift lever apparatus is provided with a so-called key interlock mechanism. The key interlock mechanism only enables the removal of an ignition key from a key cylinder into which it has been inserted when the shift lever is shifted to a shift position corresponding to a parking range which is a shift range for locking the wheels of a vehicle (hereinafter, this shift position is referred to as xe2x80x9cP positionxe2x80x9d, for convenience of explanation).
More specifically, the key interlock mechanism is provided in the key cylinder, and includes: a cam which is rotated together with the rotation of the ignition key inserted into the key cylinder; and a lock member which is provided so as to be able to reciprocate between a lock position on the locus of rotation of the cam and a lock release position separated from the lock position. If the ignition key is positioned at a rotation position other than a position enabling the removal of the ignition key from the key cylinder, and if the shift lever is positioned at a shift position other than the xe2x80x9cP positionxe2x80x9d, the aforesaid lock member is positioned on the locus of rotation of the cam so as to restrict the rotation of the cam by a rotation of the ignition key to a position allowing the removal of the ignition key from the key cylinder. Then, when the shift lever is shifted to the xe2x80x9cP positionxe2x80x9d from the aforesaid state, the lock member is separated from the locus of rotation of the cam so that the ignition key can be rotated to a position allowing the removal of the ignition key from the key cylinder.
In general, mechanical type mechanisms and electrical type mechanisms are used for moving the lock member.
Mechanical type mechanisms include a cam follower which is displaced by being directly or indirectly pressed by a shift lever being shifted to the xe2x80x9cP positionxe2x80x9d, and a cable connecting the cam follower and the lock member. When the shift lever moves the cam follower as it is shifted to the xe2x80x9cP positionxe2x80x9d, the cam follower operates and moves the lock member via the cable.
On the other hand, the electrical type mechanism includes a solenoid for moving the lock member by magnetic force, a control device such as a computer for controlling the solenoid, and a switch for detecting that the shift lever has been shifted to the xe2x80x9cP positionxe2x80x9d. When the switch detects that the shift lever has been shifted to the xe2x80x9cP positionxe2x80x9d, the control device energizes the solenoid or terminates the flow of current to the solenoid, thus enabling the lock member to be moved.
Note that, in general, the shift lever apparatus is provided between a driver""s seat and a passenger seat of a vehicle, while the key cylinder is provided in a steering column cover separated from the position of the shift lever apparatus. For this reason, in a mechanical type key interlock mechanism, there is a need to secure space for arranging cables, and the task of arranging the cables is complicated. In addition, adjustment is required when the cables are being arranged so that the mechanism will definitely operate. In contrast, an electrical type key interlock mechanism has none of the problems described above. However, in the electrical type key interlock mechanism the individual constituent members and devices are expensive causing the overall cost to be increased.
In view of the above, the object of the present invention is to provide a low cost shift lever apparatus equipped with a key interlock mechanism.
To achieve the above object, the present invention is a shift lever apparatus for shifting a shift lever connected to a vehicle transmission into a shift range from among a plurality of set shift ranges in the vehicle transmission which corresponds to a position to which the shift lever has been moved by a manual shift operation comprising a key device which is provided adjacent to a side of the shift lever and holds an ignition key which has been inserted inside the key device and can be operated by being rotated, and which key device restricts removal of the ignition key other than at a predetermined removal position, and a lock link which restricts rotation of the ignition key to a removal position inside the key device, as well as releases the restriction on the rotation of the ignition key when displaced by a predetermined operation of the shift lever occurring at a specific shift position corresponding to a specific shift range from among the plurality of shift ranges.
In the shift lever apparatus having the structure as described above, when the shift lever is positioned in a shift position other than a specific shift position corresponding to a specific shift range from among the plurality of shift ranges set in the transmission (e.g., a parking range in which the transmission of driving force to a driving wheel of a vehicle is cut off and the driving wheel is locked), the lock link directly or indirectly prevents the rotation of the ignition key to the extraction position inside the key device. Therefore, in this state, it is impossible to extract the ignition key from the key device (key interlock), and, for example, by extracting the ignition key from the key device, the key device is made unable to lock a steering wheel which forms part of the steering unit (Note that this steering lock mechanism is not an indispensable element in the present invention, and is merely used as an example).
When the shift lever is manually shifted to a specific shift position from the aforesaid state, and a predetermined operation of the shift lever is carried out, the lock link is displaced so as to release the restriction of rotation of the ignition key by the lock link. In this state, by rotating the ignition key to the extraction position, it becomes possible to extract the ignition key from the key device For example, if the aforesaid steering lock mechanism is interlocked with the key device, by extracting the ignition key from the key device, it is possible to lock the steering wheel.
As described above, in the present invention, the lock link restricts the rotation of the ignition key to the extraction position by an engagement of engaging members provided in the shift lever, and releases the restriction of the rotation by releasing the engagement of the engaging members. In addition, because the key cylinder is provided at a side of the shift lever, there is no need to provide cables between the shift lever apparatus and the key cylinder as in a conventional shift lever apparatus. Thus, it is possible to dispense with troublesome tasks such as having to adjust the cables when assembling the conventional shift lever apparatus. Further, basically, the only component constituting the key interlock mechanism is the lock link; therefore, a cost reduction can be achieved.
Moreover, by providing the key cylinder and the shift lever in close proximity to each other, the key cylinder and the shift lever can be constituted as a unit (provided as an assembled part). Therefore, mounting the key cylinder and shift lever on a vehicle is made easier.
Note that, in a conventional shift lever apparatus, a manual operation to rotate the shift lever taking the transverse direction of the vehicle as the axial direction is called a shift operation, and an operation to rotate the shift lever with the longitudinal direction of the vehicle as the axial direction is called a select operation. However, in the present invention, the term xe2x80x9cshift operationxe2x80x9d is not limited to an operation to rotate the shift lever using the transverse direction of the vehicle as the axial direction. Namely, the operation of changing the transmission shift range is called a shift operation regardless of the direction and type of movement of the shift lever.
Accordingly, for example, a shift lever shift operation of what is known as a gate-type shift lever apparatus for changing the shift range of a transmission by moving the shift lever in a zigzag direction in the longitudinal and transverse directions of the vehicle is also categorized as a xe2x80x9cshift operationxe2x80x9d.
Further, the present invention is preferably the shift lever apparatus further comprising a detent pin connectable to the shift lever so as to protrude therefrom towards the key device side, which detent pin is able to move integrally with the shift lever in the manual shift operation direction, and which detent pin moves in a direction orthogonal to the manual shift operation direction when a predetermined release operation is carried out, and a detent section interposed between the shift lever and the key device, in which is formed a detent hole into which the distal end of the detent pin is inserted, with a restricting section formed inside the detent hole for restricting movement of the detent pin by abutting the detent pin on the locus of the movement of the detent pin which accompanies a manual shift operation of the shift lever to the specific shift position and restricts movement of the detent pin, and which restricting section is able to be avoided by the detent pin via a specific release operation, wherein, when the shift lever is positioned in a specific shift position, the detent pin, having avoided the restricting means, engages with the lock link when the detent pin returns to a state before the release operation was performed, and displaces the lock link to a position at which the restriction on the rotation of the ignition key is released.
In the shift lever apparatus having the structure described above, when the shift lever is manually shifted to a specific shift position, the detent pin provided in the shift lever abuts against the restricting portion formed in the inner peripheral portion of the detent opening of the detent portion so as to restrict movement of the detent pin accompanying the shift operation of the shift lever. Whereby the shift operation of the shift lever to the specific shift position is indirectly restricted by the restricting portion via the detent pin, and thus, it is possible to restrict a careless shift operation to the specific shift position.
In this state, when a predetermined release operation is carried out, the detent pin is moved to a position capable of avoiding the restricting portion toward a direction intersecting-with respect to the shifting direction. Therefore, in this state, the restriction of shift operation by the restricting portion is released, and thus, the shift lever can be shifted to the specific shift position.
Subsequently, in this state, when the aforesaid predetermined release operation is further released so as to return the detent pin to a state before the predetermined release operation is carried out, the detent pin is engaged with the lock link so as to displace the lock link, and then, a restriction of rotation of the ignition key by the lock link is released. In this state, the ignition key is rotated to the removal position, and thereby, it is possible to pull out the ignition key from the key device.
According to the present invention, preferably, the shift lever apparatus includes a base member which is provided with the key device, and supports the shift lever so as to shift the shift lever, and further, is formed with the detent portion.
In the shift lever apparatus having the construction as described above, the base member is provided with the key device, and the shift lever is supported to the base member, and further, the aforesaid detent portion is formed in the base member. Namely, in the present invention, the shift lever, the key device and the detent portion are integrally assembled by the base member. Therefore, it is possible to perform an adjustment for the lock link and the detent pin before mounting these members to a vehicle; as a result, assembly of these members to a vehicle can be readily performed.